Getting Feedback

You may never know when it’s going to strike, you will see people cower and cover their ears and everyone will look to each for answers …no I’m not talking about an air strike I’m talking about audio feedback loops.

As a live sound engineer one of my main concerns (and I’m sure I’m not alone) is the ear piercing feedback loop noise that ensures the band will never hire you again.

After doing some research  it seems as though  managing feedback can  become second nature, as long as you keep in mind some rules and techniques. This is just a brief checklist for me for the stage I am at.

If you get the chance before sound check, perform a procedure called “ringing out”. This entails first setting the desk faders to unity and then turning up the gain pots one at a time until you hear it start to feedback.  Take note of when it starts to occur and then back the pot off by roughly 5dB, mark a line on some tape or write a reminder on a strip of tape along the top of the gain pots.  Once all microphones have been tested check all microphones together and you may have to back each one off slightly again. During the show you then mix with the faders, not with the pots and this will limit the risk of feedback.The side benefit of  not riding the gain pots and using the faders means your fold-back mixes will not be  disturbed as the amount of signal being sent through the fold backs pre-fader but not pre gain. This saves the band having alternating feedback levels during the show

Know the room and the potential problem areas. During sound check play some music and push some frequencies. See if you identify some problem areas and cut them out without sacrificing too much of the sound. This is also a good time to get some clarity EQ wise (using your voice is a great reference as you've listened to it your whole life!)

Know your microphone polar patterns, fold back positioning, side fill positioning, musician positioning and instrument/amp positioning.  Make sure all potential feedback angles are facing microphone nulls (as best as possible).

Take note of how the musicians use the microphones during sound check and if you get the chance ask some questions on how they perform. Do they get up nice and close? Do they stand back to far? Do they walk around the stage?  If they do stand back and you have to increase the gain be wary of feedback.

A big thing I noticed last week was how if you couple the microphone to much it starts to feedback. Not only that, musicians who wear hats and other accessories can cause the same effect, something to be mindful of.

There is a lot of considerations with live sound and this is just one aspect. On the plus side  these techniques and rules go hand in hand with other aspects of live sound. I look forward to “ringing out” this week and getting some live sound disciplines developing.

Appleton, Harvey. (2012, 19 December). 18 Ways to Reduce Feedback in Live Sound Engineering. Retrieved from

White, Paul. (2013, March). Preventing Acoustic Feedback On Stage. Retrieved from